


astrum

by Anonymous



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Crack, Gen, Magical Boys, Male My Unit | Byleth
Language: English
Status: In-Progress
Published: 2019-12-20
Updated: 2019-12-22
Packaged: 2021-02-26 06:35:07
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 1,697
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21869113
Author URL: https://archiveofourown.org/
Summary: If merging with Sothis had a different affect...
Kudos: 27
Collections: anonymous





	1. A Farewell Between Friends (Goodbye to the Goddess)

**Notes for the Chapter:**

> no actual magical guy byleth right now, i really just wanted to build up the relationship between him and sothis
> 
> besides, isnt it just like the genre to have this really blown out and emotional scene before the first transformation.

“Professor-” was the last thing Byleth heard before the darkness of Solon’s spell swallowed him, cutting him off from the students.

The dark was cold, a freezing chill that managed to bite through his defenses, practically eating away at him. The silence was malevolent, always seeming to assault his senses as he curled up, the touch of his own skin the only feeling that the world around him could currently give.

After a while, he suddenly felt himself fall, landing against hard stone with a gasp. The light changed as he stood up, showing the familiar throne and goddess sitting in it. “You fool! What were you thinking, charging right into an enemy’s trap?”

“I can explain-”

“Are you just a boulder that rolls down whatever hill it’s on?” She continued to shout, “No! Even a boulder has more sense!”

Sensing the end of her tirade Byleth smiled sadly as he started walking towards the throne. “I’m sorry.”

Sothis sighed. “As you and I are one, I, too, am trapped within this void. It would take a god to leave this place.” She makes eye contact with the mercenary as she speaks. “In time, our hearts and minds will cease to be. Are you prepared to die?”

It’s an empty question. They both know the answer. Byleth doesn’t even have to say it.

_ I am not. _

“I thought as much.” Sothis said, her face softening as Byleth reached the foot of the throne. “I also do not wish to die. And yet, there is no other choice…”

Confusion struck Byleth. “What choice?”

Sothis looked sad. “Do you recall your father's diary? He said you were a child who never cried nor laughed. I think I am the one to blame. I must have been asleep, but even then, I feel I was a part of you. I do not know how Rhea managed it, but she allowed me to exist inside of you. The truth is I have always been with you. It is within you that I found my power yet again. The power of a goddess. The power of the progenitor god.”

Byleth stayed silent, a clear sign for Sothis to continue speaking.

"By now you must be well aware of what that means.” She said. He did. “I am the one who watches over Fodlan and the creatures dwelling there. I am Sothis, she who died then returned.”

“I still can’t believe it.” He said softly, taking a seat next to the throne.

“I know.” Sothis laughed. “The time has come for you and I to join as one. And when that comes to pass… I shall disappear.”

“Disappear?!”

“My soul will join with yours, and you and I will never be apart. But...I will no longer have a chance to speak with you.” Sothis explained, soothing Byleth’s fears. “I shall miss it. I got to see and hear this world. I even got to chastise you from time to time.” She sighed, and Byleth heard her shift her weight and looked up to see her sitting on the side of her throne. “I may not have acted like a goddess, but it was certainly fun. I’m glad it was to you that my fate has been bound.”

Byleth gave one last, weak smile as he stood up, feeling the mood of the room shift and anticipating her to begin the process. “Thank you-”  _ for being there, for scolding me, for turning back time, for helping me through dad’s-  _ “for everything.”

Sothis smiled back as she started to glow. There was no need for her to say a welcome. Byleth could already feel it.


	2. A Transformation of Tribute (Professor of Power)

**Notes for the Chapter:**

> yeah, this is just crack, but it has it's good moments.
> 
> also (this is edited in later) i 100% took liberties with the sothis regalia outfit for mbyleth because he deserves to show off

_ Awake to your power. I have shared it with you for quite some time now, try to do the same with others. _

* * *

“Unless I dispose of you myself-” Solon rambled, backing away from Byleth as his eyes readjusted to the light, “I may never have the chance to send you back there!”

The Blue Lions watched as more enemies warped around the forest, and Byleth readied the Sword of the Creator as Ingrid flew behind him for support. Looking at the armored knight in front of him, Byleth saw both a strong red and a faint purple light coming from the unit. Using the sword as a staff, he quickly sent two fireballs at them, the armored knight going down in flames.

Moving forward, Byleth caught up to Felix as the student’s battalion was engaged in battle with a monster The sword had never felt like such an extension to his arm as he slipped past it’s claw and stabbed twice, the sound of the blade’s song as it sliced through the air nearly heavenly and divine in the chaos of the battle.

Byleth dodged a swing coming from another mysterious soldier, his own weapon quickly cutting them down as if it was barely a reaction. He heard Cyril and Felix defeat the monster as he quickly dashed up the hill to catch Solon, the Sword of the Creator humming a deep, warning tone as it got closer to the man.

Solon was at the top of a small altar before he turned around, seemingly ready to take a final stand on the hallowed ground. Byleth slowed down to a small walk, practically stalking his way along the grass as he heard the mage speak. “I am terrified by you, even though an emotion like fear has no place inside me.” 

Byleth stopped, staring Solon down. His anger rose up in him again, but with a sense of peace that steadied his hand better than the apathy he had been using as a mercenary ever did. He barely heard Solon finish speaking before he slashed with his sword, a pained and warbled screech emantating in harmony with the blade as Solon fell off the altar, dead.

Byleth flicked the sword to get any excess blood off of it as he saw Dimitri run up to him. The prince bowed as he reached Byleth, a warm smile on his face. “Professor, I’m glad you’re okay. You seem relatively unscathed-”

Dimitri hesitated, seemingly unsure of what to say next, and as Byleth sheathed the sword, Dimitri spoke again. “I’m so relieved. What happened after we were separated? You look-” Dimitri blushed as he hesitated once again, staring directly at Byleth, “different.”

Byleth looked down at himself and was shocked at what his clothes had become. The light armor he had grown used to wearing was gone, his upper torso now adorned in trails of gold jewelry and pendants connected to a piece of purple fabric shaped to cover his throat and shoulders, separate strings of white and pink ribbons looping around his arms to snugly secure the piece to his skin. His legs were mostly bare, the small purple shorts that stopped midthigh and the intricate sandals not even practically covered by the open “skirt” that fell to his knees, the right side of it pressed down by the sword sheath. He felt a weight on his head and reached up, lightly touching the tiara in his hair.

He opened his mouth to speak before he realized no sound was coming out of it. Dimitri seemed to understand his plight moved closer, carefully placing a hand on his shoulder. Byleth felt something in his gut tighten, and suddenly memories were replaying in his head.

_ His first dreams, Sothis, Divine Pulse, their last conversation- _

Dimitri took a sharp breath as he removed his hand. “The goddess appeared and gave you her power? It’s as though the legend of old has been made flesh. But still, I find myself unable to doubt it.” 

Byleth tried to speak again, wanting to ask what Dimitri was talking about before he shook his head, tapping the man’s chest again. Dimitri paused, but then nodded, as if he had gotten the gist of what the mercenary had asked for.

“Yes.The legend of Saint Seiros-” Dimitri said, launching into an in depth explanation as the house started making their way out of the forest. Byleth fell into step with him as they moved, glad that Dimitri was starting to look better after the events at Remire.

The exhaustion hit him suddenly, a gasp falling out of his mouth the only warning before he felt himself shutdown, passing out next to his student.

* * *

_ Professor! What’s wrong?! Are you- _

_ Are you asleep? _

_ We must get you help, and fast. _

_ Sorry Professor, I have no choice but to carry you back. _

* * *

Byleth woke up to Rhea singing, her voice fading out as she reached the end of the verse. He opened his eyes and tried to sit up, only for Rhea to gently push him back down to rest. “Professor.” She said, a small smile on her face. “You must remain still.”

Her hand was still on his chest.  _ Where am I? What happened? Is everyone- _

She took it off, taking a seat on the edge of the bed. “Everything is alright. There is no need to worry.” 

The sunlight from an unseen window hit Byleth’s face, obscuring his vision as he squinted. Rhea kept on humming as she worked, the same tune that Sothis would occasionally sing.

“I wish I could hold onto this moment.” Rhea said. “But your appearance means that you have received power from the goddess. The Sword of the Creator, in all of it’s celestial light, fully belongs to you. But you are more than the light, you are my-” 

Rhea cut herself off, looking away from Byleth as she got off of the bed, walking towards the opened window and closing it. “Close your eyes, dear one.” Her voice whispered in the now darker chambers. “Sleep, just a while longer. I will watch over you and your class.”

* * *

He first ran into Flayn as he made his way down the tower, waving to her as she waved back excitedly.

* * *

“How can I help?”

“That’s weird, right?”

“I have a feeling something big is coming.”

“-people whose hair changes color-”

“Don’t worry, it won’t hurt a bit.”

“They have qualities that are not unlike what you are looking like, Professor.”

“Have you seen his abs!?”


End file.
